Exhibit 10.31

                           Enzon Pharmaceuticals, Inc.
                      Executive Deferred Compensation Plan

1.    Statement of Purpose

      The purpose of the Enzon Pharmaceuticals, Inc. Executive Deferred
      Compensation Plan (the "Plan") is to aid Enzon Pharmaceuticals, Inc. (the
      "Company") and its subsidiaries in attracting and retaining key employees
      by providing a non-qualified compensation deferral vehicle.

2.    Definitions

      2.01  Annual Incentive Compensation - "Annual Incentive Compensation"
            means the amount paid annually to the Participant under the Enzon
            Pharmaceuticals Management Incentive Plan before reductions for
            deferrals under this Plan or the Enzon Inc. Savings and Investment
            Plan.

      2.02  Average Treasury Rate - "Average Treasury Rate" means the interest
            crediting rate used to determine the amount of interest credited to
            a Participant's Deferred Compensation Account under Section 6.02 and
            6.03. The rate for a Calendar Quarter shall be determined by
            averaging the Monthly Rates for 10-year Treasury bonds during the
            Calendar Quarter. The Monthly Rate for each month shall be the yield
            on 10-year Treasury bonds as calculated by Bloomberg Business News
            on the first business day of each month. If it becomes necessary to
            determine the value of that portion of a Participant's Deferred
            Compensation Account during a Calendar Quarter, but before the
            Average Treasury Rate for the Calendar Quarter can be determined,
            the Average Treasury Rate for the portion of the Calendar Quarter
            for the Participant's Deferred Compensation Account shall equal the
            average of the available Monthly Rates for the Calendar Quarter up
            to the Distribution Date.


      2.03  Base Salary - "Base Salary" means the Participant's annual basic
            rate of pay from the Company excluding Annual Incentive Compensation
            and other non-regular forms of compensation before reductions for
            deferrals under this Plan or the Enzon Pharmaceuticals, Inc. Savings
            and Investment Plan.

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      2.04  Beneficiary - "Beneficiary" means the person or persons designated
            as such in accordance with Section 8.


      2.05  Board of Directors - "Board of Directors" means the Board of
            Directors of the Company.

      2.06  Calendar Quarter - "Calendar Quarter" means any of the four calendar
            quarters in a full calendar year (e.g. January, February & March
            comprise the first calendar quarter).

      2.07  Committee - "Committee" means the Vice President, Human Resources,
            Chief Financial Officer and Chief Executive Officer.

      2.08  Cycle - "Cycle" means the twelve-month pay-in period for each
            deferral. The first Cycle shall begin on January 1, 2004 and end on
            December 31, 2004. The following Cycles shall begin on January 1 of
            each year and end on December 31 each year.

      2.09  Deferral Amount - "Deferral Amount" means the total amount of
            Elective Deferred Compensation and/or Non-Elective Deferred
            Compensation actually deferred by the Participant.

      2.10  Deferred Compensation Account - "Deferred Compensation Account"
            means the account maintained on the books of account of the Company
            for a Participant pursuant to Section 6.

      2.11  Disability - "Disability" means the Participant is eligible to
            receive benefits under a long term disability plan maintained by the
            Company.

      2.12  Distribution Date - "Distribution Date" means the date on which the
            Company makes distributions from the Participant's Deferred
            Compensation Account(s).

      2.13  Effective Date - "Effective Date" means the date on which this Plan
            is effective, November 1, 2003.

      2.14  Election Form - "Election Form" means the form or forms attached to
            this Plan and filed with the Company by the Participant in order to
            participate in the Plan. The terms and conditions specified in the
            Election Form(s) are incorporated by reference herein and form a
            part of the Plan.

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      2.15  Elective Deferred Compensation - "Elective Deferred Compensation"
            means the total amount elected to be deferred by an Eligible
            Employee on his/her Election Form.

      2.16  Eligible Employee - "Eligible Employee" means any employee of the
            Company who is a Vice-President or higher, or such other key
            executives of the Company as may be designated by the Committee.

      2.17  Non-Elective Deferred Compensation - "Non-Elective Deferred
            Compensation" means the amount awarded to a Participant by the Board
            of Directors of the Company pursuant to Section 4.

      2.18  Participant - "Participant" means an Eligible Employee participating
            in the Plan in accordance with the provisions of Section 4.

      2.19  Plan Year - "Plan Year" means the twelve month period beginning on
            the first day of the first Cycle in which the Eligible Employee
            elects to participate in the Plan. The initial Plan Year will
            commence on the January 1, 2004 and end on December 31, 2004. Each
            later Plan year will begin on January 1 and end on December 31.

      2.20  Related Employment - "Related Employment" means the employment of a
            Participant by an employer that is not the Company, provided (i)
            such employment is undertaken by the Participant at the request of
            the Company; (ii) immediately prior to undertaking such employment,
            the Participant was an employee of the Company, or was engaged in
            Related Employment as herein defined; and (iii) such employment is
            recognized by the Committee, in its sole discretion, as Related
            Employment.

      2.21  Substantially Equal Installments - "Substantially Equal
            Installments" means a series of annual payments, such that equal
            payments over the remaining payment period would exactly amortize
            the Participant's Deferred Compensation Account balance as of the
            Distribution Date if the investment return remained constant at the
            return credited as of the Valuation Date immediately preceding the
            Distribution Date for the remainder of the payment period.

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      2.22  Termination of Employment - "Termination of Employment" means the
            end of a Participant's employment with the Company for any reason
            other than Disability, Related Employment, or the termination of a
            Participant's Related Employment if the Participant returns to the
            Company.

      2.23  Valuation Date - "Valuation Date" means the date on which the value
            of a Participant's Deferred Compensation Account is determined for
            each Calendar Quarter as provided in Section 6 hereof. Unless and
            until changed by the Committee, the Valuation Dates within each
            Cycle shall be the last day of each of the four Calendar Quarters of
            the calendar year.

      2.24  Years of Service - "Years of Service" means the cumulative years of
            continuous full-time employment with the Company beginning on the
            date the Participant first began service and each anniversary
            thereof.

3.    Administration of the Plan

      3.01  Plan Administration. The Committee shall be the sole administrator
            of the Plan, and will administer the Plan. The Committee shall have
            the power to formulate additional details and regulations for
            carrying out this Plan. The Committee also shall be empowered to
            make any and all determinations not authorized specifically herein
            that may be necessary or desirable for the effective administration
            of the Plan. Any decision or interpretation of any provision of this
            Plan adopted by the Committee shall be final and conclusive.

      3.02  Delegation of Duties. The Committee may delegate any or all of its
            duties as to the administration of this Plan to other individuals or
            groups of individuals within the Company, as it deems appropriate.

4.    Participation

      4.01  Elective Participation.

            a.    Any Eligible Employee may elect to participate in the Plan for
                  a given Cycle by filing a completed Election Form for the
                  Cycle with the Company. With regard to an election to
                  participate:

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                  i.    The Election Form must be filed with the Company prior
                        to the commencement of the Cycle to which the Election
                        Form pertains, or at such earlier time as determined by
                        the Company.

                  ii.   The minimum deferral for a Cycle shall be $5,000.

                  iii.  The maximum deferral shall be fifty percent (50%) of the
                        Participant's Base Salary (as defined in Section 2.03)
                        and one hundred percent (100%) of Participant's Annual
                        Incentive Compensation (as defined in Section 2.01).
                        Provided, however, that no election will be effective to
                        reduce amounts paid by the Company to an Eligible
                        Employee to an amount which is less than the sum of the
                        amount the Company is required to withhold for a Cycle
                        for purposes of federal, state, and local income taxes,
                        including FICA tax withholding and the amount the
                        Company is required to withhold for contributions to any
                        employee benefit plan (other than this Plan).

                  iv.   A Participant may elect to receive payment of amounts
                        deferred during a Cycle upon Termination of Employment,
                        or in a specified year which shall be no earlier than in
                        the third cycle following the Cycle in which such
                        amounts are deferred. Further, a Participant may elect
                        to receive payment in a lump-sum or in up to fifteen
                        (15) annual installments.

            b.    A Participant's election to defer future Compensation is
                  irrevocable upon the filing of his/her Election Form with the
                  Company, provided, however, that the election may be
                  terminated with respect to Compensation not yet earned by
                  mutual agreement in writing between the Participant and the
                  Company.

4.02  Non-Elective Participation. The Committee can, in its sole discretion,
      award to an Eligible Employee Non-Elective Deferred Compensation. Unless
      otherwise specified by the Committee, the Participant shall determine,
      subject to Section 4.01a(iv), the timing and form of payment of any
      Non-Elective Deferred Compensation at the time it is awarded.

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5.    Vesting of Deferred Compensation Account

      A Participant's interest in his/her Deferred Compensation Account shall
      vest immediately.

6.    Accounts and Valuations

      6.01  Deferred Compensation Accounts. The Committee shall establish and
            maintain a separate Deferred Compensation Account for each
            Participant for each Cycle. Deferred amounts will be credited to a
            Participant's account on the first day of the month following the
            time at which the amount would otherwise have been paid. Any
            Non-Elective Deferred Compensation awarded to a Participant shall be
            credited to the Participant's Deferred Compensation Account on such
            date as specified by the Committee.

      6.02  Interest Rate Credited. The Participant's Deferred Compensation
            Account shall be credited with interest quarterly at a rate equal to
            the Average Treasury Rate plus three percentage points (3%). The
            Committee shall review the interest rate on an annual basis and may
            increase or decrease the interest rate credited on a prospective
            basis. Any such change in the interest rate credited shall be made
            60 days before the end of the Plan Year preceding the year in which
            the interest crediting rate changes. Written notice of any such
            change in interest rate shall be given to each Participant in the
            Plan.

      6.03  Timing of Crediting of Interest. The Participant's Deferred
            Compensation Account shall be revalued and credited with interest as
            of each Valuation Date. As of each Valuation Date, the value of the
            Participant's Deferred Compensation Account shall consist of the
            balance as of the immediately preceding Valuation Date, plus the
            amount of any Elective and Non-Elective Deferred Compensation
            credited since the preceding Valuation Date, minus the amount of all
            distributions, if any, made from such Deferred Compensation Account
            since the preceding Valuation Date. As of each Valuation Date,
            interest shall be credited on the value of the Participant's
            Deferred Compensation Account as of such date.

      6.04  Excess 401(K) Matching Credit. At the end of each Plan Year, a
            Participant's Deferred Compensation Account will be credited with an
            Excess 401(K) Matching Credit as follows:

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            a.    Matchable Annual Deferral. The Matchable Annual Deferral shall
                  be that portion of a Participant's Deferral Amount for each
                  Cycle which is less than or equal to: (i) six percent (6%) of
                  the total Base Salary plus Annual Incentive Compensation for a
                  Cycle minus (ii) the amount of Elective Contribution to the
                  Enzon Pharmaceuticals, Inc. 401(K) Savings and Investment Plan
                  made by the Participant for which the Participant received an
                  Employer Matching Contribution under the Enzon
                  Pharmaceuticals, Inc. 401(K) Savings and Investment Plan for
                  the same Cycle. However, if the Participant does not make the
                  maximum allowable deferral to the Enzon Pharmaceuticals, Inc.
                  401(K) Savings and Investment Plan for any Cycle, the
                  Matchable Annual Deferral for such Cycle shall be zero.

            b.    Excess 401(K) Matching Credit. The Excess 401(K) Matching
                  Credit shall be 50% of the value of the Matchable Annual
                  Deferral for the Cycle.

            c.    Vesting. The Participant's right to receive the Excess 401(K)
                  Matching Credits credited to the Participant's Deferred
                  Compensation Account in the event of Termination of Employment
                  prior to reaching age 55 shall vest in accordance with the
                  following schedule:



                   Completed Years of Service   Vested Percentage
                   --------------------------   -----------------
                               0-1                        0%
                               1-2                       20%
                               2-3                       40%
                               3-4                       60%
                               4-5                       80%
                                5+                       100%

      6.05  Distributions. For the purpose of crediting interest pursuant to
            Sections 6.02 and 6.03, any distributions made during a Calendar
            Quarter shall be deemed to have been made on the first day of such
            quarter.

      6.06  Nature of Account Entries. The establishment and maintenance of
            Participants' Deferred Compensation Accounts and the crediting of
            gains and losses pursuant to this Section 6 shall be merely
            bookkeeping entries and shall

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            not be construed as giving any person any interest in any specific
            assets of the Company or of any subsidiary of the Company or any
            trust created by the Company, including any investments owned by the
            Company or any such subsidiary or trust. The hypothetical investment
            of the Participant's Deferred Compensation Accounts shall be for
            bookkeeping purposes only, and shall not require the establishment
            of actual corresponding funds or investments by the Committee or the
            Company. Benefits accrued under this Plan shall constitute an
            unsecured general obligation of the Company.

7.    Benefits

      7.01  Normal Benefit

            a.    A Participant's Deferred Compensation Account shall be paid to
                  the Participant in accordance with the terms of the
                  Participant's Election Form, subject to the terms and
                  conditions specified in the Election Form. If a Participant
                  elects to receive payment of his/her Deferred Compensation
                  Account in installments, subject to a maximum of fifteen (15)
                  installments, payments shall be made in Substantially Equal
                  Installments. Unless the Committee determines otherwise, and
                  subject to the provisions of Section 7.04 as to when payments
                  shall commence, installments shall be paid on the 15th day of
                  February of each year.

            b.    Notwithstanding the provisions of Section 7.01a, and
                  notwithstanding any contrary election made by the Participant
                  on his/her Election Form, if a Participant has a Termination
                  of Employment, and if the Participant at the time of his/her
                  Termination of Employment, is less than 50 years of age and
                  has not completed three (3) Years of Service, the
                  Participant's Deferred Compensation Account balance will be
                  paid to the Participant in a lump-sum in the year following
                  the Participant's Termination of Employment. However, upon the
                  written request of the Participant, the Committee, in its sole
                  discretion, may allow payments to be made to the Participant
                  in up to fifteen (15) annual installments.

            c.    In the event of a Participant's death before a complete
                  distribution of his or her account, the Participant's
                  designated Beneficiary will receive an amount equal to the
                  Participant's Deferred Compensation Account, and

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                  such amount shall be paid in a single sum or annual
                  installments (not to exceed 10) in accordance with the
                  Participant's election. However, the Committee may, in its
                  sole discretion, pay the Participant's remaining account
                  balance in a single sum if so requested by the Participant's
                  Beneficiary.

      7.02  Hardship Benefit. In the event that the Committee, upon written
            petition of the Participant, determines in its sole discretion, that
            the Participant has suffered an unforeseeable financial emergency,
            the Company may pay to the Participant, as soon as is practicable
            following such determination, an amount necessary to meet the
            emergency, not in excess of the Deferred Compensation Account
            credited to the Participant. The Deferred Compensation Account of
            the Participant thereafter shall be reduced to reflect the payment
            of a Hardship Benefit.

      7.03  Taxes; Withholding. To the extent required by law, the Company shall
            withhold from payments made hereunder an amount equal to at least
            the minimum taxes required to be withheld by the federal, or any
            state or local, government.

      7.04  Date of Payments. Except as otherwise provided in this Plan,
            payments under this Plan shall begin on or before the 15th day of
            February of the calendar year following receipt of notice by the
            Committee of an event that entitles a Participant (or Beneficiary)
            to payments under the Plan, or at such earlier date as may be
            determined by the Committee.

8.    Beneficiary Designation

      At any time prior to complete distribution of the benefits due to a
      Participant under the Plan, he/she shall have the right to designate,
      change, and/or cancel, any person(s) or entity as his/her Beneficiary
      (either primary or contingent) to whom payment under this Plan shall be
      made in the event of his/her death. Each beneficiary designation shall
      become effective only when filed in writing with the Company during the
      Participant's lifetime on a form provided by the Company. The filing of a
      new beneficiary designation form will cancel all previously filed
      beneficiary designations. Further, any finalized divorce of a Participant
      subsequent to the date of filing of a beneficiary designation form in
      favor of Participant's spouse shall revoke such designation.

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      Additionally, the spouse of a Participant domiciled in a community
      property jurisdiction shall join in any designation of Beneficiary other
      than the spouse.

      If a Participant fails to designate a Beneficiary as provided above, or if
      his/her beneficiary designation is revoked by divorce or otherwise without
      execution of a new designation, or if all designated Beneficiaries
      predecease the Participant, then the distribution of such benefits shall
      be made to the Participant's estate. If a Beneficiary survives the
      Participant but dies before receiving a complete distribution of benefits,
      any remaining amount shall be paid to the estate of such Beneficiary in a
      lump-sum.

9.    Amendment and Termination of Plan

      9.01  Amendment. The Committee may amend the Plan at any time in whole or
            in part, provided, however, that, except as provided in Section 9.02
            and Section 6.02, no amendment shall be effective to decrease the
            benefits under the Plan payable to any Participant or Beneficiary
            with respect to any Elective or Non-Elective Deferred Compensation
            deferred prior to the date of the amendment. Written notice of any
            amendments (other than amendments that are administrative in nature)
            shall be given to each Participant in the Plan.

      9.02  Termination of Plan

            a.    Company's Right to Terminate. The Committee may terminate the
                  Plan at any time.

            b.    Payments Upon Termination. Upon any termination of the Plan
                  under this section, Compensation shall cease to be deferred
                  prospectively, and, with respect to Compensation deferred
                  previously, the Company will pay to the Participant (or the
                  Participant's Beneficiary, if after the Participant's death),
                  in a lump-sum, the value of his/her Deferred Compensation
                  Account.

10.   Miscellaneous

      10.01 Unsecured General Creditor. Participants and their beneficiaries,
            heirs, successors and assignees shall have no legal or equitable
            rights, interests, or other claims in any property or assets of the
            Company, nor shall they be beneficiaries of, or have any rights,
            claims, or interests in any life insurance

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            policies, annuity contracts, or the policies therefrom owned or that
            may be acquired by the Company ("policies"). Such policies or other
            assets of the Company shall not be held in any way as collateral
            security for the fulfilling of the obligations of the Company under
            this Plan. Any and all of the Company's assets and policies shall be
            and will remain general, unpledged, unrestricted assets of the
            Company. The Company's obligation under the Plan shall be that of an
            unfunded and unsecured promise of the Company to pay money in the
            future.

      10.02 Grantor Trust. Although the Company is responsible for the payment
            of all benefits under the Plan, the Company, in its sole discretion,
            may contribute funds as it deems appropriate to a grantor trust for
            the purpose of paying benefits under this Plan. Such trust may be
            irrevocable, but assets of the trust shall be subject to the claims
            of creditors of the Company. To the extent any benefits provided
            under the Plan actually are paid from the trust, the Company shall
            have no further obligation with respect thereto, but to the extent
            not so paid, such benefits shall remain the obligation of, and shall
            be paid by, the Company. Participants shall have the status of
            unsecured creditors on any legal claim for benefits under the Plan,
            and shall have no security interest in any such grantor trust.

      10.03 Successors and Mergers, Consolidations or Change in Control. The
            terms and conditions of this Plan shall inure to the benefit of the
            Participants and shall bind the Company, its successors, assignees,
            and personal representatives. If substantially all of the stock or
            assets of the Company are acquired by another entity, or if the
            Company is merged into, or consolidated with, another entity, then
            the obligations created hereunder shall be obligations of the
            acquirer or successor entity.

      10.04 Non-Assignability. Neither a Participant, nor any other person,
            shall have any right to commute, sell, assign, transfer, pledge,
            anticipate, mortgage or otherwise encumber, transfer, hypothecate,
            or convey in advance of the actual receipt, any amounts payable
            hereunder, or any part thereof. All rights to payments expressly are
            declared to be unassignable and nontransferable. No part of the
            amounts payable, prior to actual payment, shall be subject to
            seizure or sequestration for the payment of any debts, judgments,
            alimony or separate maintenance owed by a Participant, or any other
            person, nor shall they be

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            transferable by operation of law in the event of a Participant's, or
            any other person's, bankruptcy or insolvency.

      10.05 Employment or Future Eligibility to Participate Not Guaranteed.
            Nothing contained in this Plan, nor any action taken hereunder,
            shall be construed as a contract of employment, or as giving any
            Eligible Employee any right to be retained in the employ of the
            Company. Designation as an Eligible Employee may be revoked at any
            time by the Committee with respect to any Compensation not yet
            deferred.

      10.06 Protective Provisions. A Participant will cooperate with the Company
            by furnishing any and all information reasonably requested by the
            Company in order to facilitate the payment of benefits hereunder,
            including, but not limited to, taking such physical examinations as
            the Company reasonably may deem necessary (if the Company purchases
            life insurance to informally fund the Plan) and taking such other
            relevant action as may be reasonably requested by the Company. If a
            Participant refuses to cooperate, the Company shall have no further
            obligation to the Participant under the Plan, except for the
            distribution to Participant of his or her Deferral Amount.

      10.07 Gender, Singular and Plural. All pronouns, and any variations
            thereof, shall be deemed to refer to the masculine, feminine, or
            neuter, as the identity of the person(s) or entity(s) may require.
            As the context may require, the singular may be read as the plural
            and the plural as the singular.

      10.08 Captions. The captions to the articles, sections, and paragraphs of
            this Plan are for convenience only and shall not control or affect
            the meaning or construction of any of its provisions.

      10.09 Applicable Law. This Plan shall be governed and construed in
            accordance with the laws of the State of New Jersey.

      10.10 Validity. In the event any provision of this Plan is found to be
            invalid, void, or unenforceable, the same shall not affect, in any
            respect whatsoever, the validity of any other provision of this
            Plan.

      10.11 Notice. Any notice or filing required or permitted to be given to
            the Company or the Committee shall be sufficient if in writing and
            hand delivered, or sent by

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            registered or certified mail, to the principal office of the Company
            at 685 North Route 202/206, Bridgewater, NJ 08807, directed to the
            attention of the Vice President, Human Resources. Such notice shall
            be deemed given as of the date of delivery or, if delivery is made
            by mail, as of the date shown on the postmark on the receipt for
            registration or certification. Any notice to the Participant shall
            be addressed to the Participant at the Participant's residence
            address as maintained in the Company's records. Any party may change
            the address for such party here set forth by giving notice of such
            change to the other parties pursuant to this Section.

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